37080 Federal Register / Vol. 63, No. 131 /Thursday, July 9, 1998 / Proposed Rules

promulgated, will not have a significant

economic impact, positive or negative,

on a substantial number of small entities

under the criteria of the Regulatory

Flexibility Act. A copy of the draft

regulatory evaluation prepared for this

action is contained in the Rules Docket.

A copy of it may be obtained by

contacting the Rules Docket at the

location provided under the caption

ADDRESSES.

List of Subjects in 14 CFR Part 39

Air transportation, Aircraft, Aviation

safety, Safety.

The Proposed Amendment

Accordingly, pursuant to the

authority delegated to me by the

Administrator, the Federal Aviation

Administration proposes to amend part

39 of the Federal Aviation Regulations

(14 CFR part 39) as follows:

PART 39—AIRWORTHINESS

DIRECTIVES

1. The authority citation for part 39

continues to read as follows:

Authority: 49 U.S.C. 106(g), 40113, 44701.

§ 39.13 [Amended]

2. Section 39.13 is amended by

removing amendment 39–9992 (62 FR

17532, April 10, 1997), and by adding

a new airworthiness directive (AD), to

read as follows:

Airbus Industrie: Docket 98–NM–01–AD.

Supersedes AD 97–08–04, Amendment

39–9992.

Applicability: Model A320 series airplanes

on which Airbus Modification 22764 has not

been installed, certificated in any category.

Note 1: This AD applies to each airplane

identified in the preceding applicability

provision, regardless of whether it has been

otherwise modified, altered, or repaired in

the area subject to the requirements of this

AD. For airplanes that have been modified,

altered, or repaired so that the performance

of the requirements of this AD is affected, the

owner/operator must request approval for an

alternative method of compliance in

accordance with paragraph (d) of this AD.

The request should include an assessment of

the effect of the modification, alteration, or

repair on the unsafe condition addressed by

this AD; and, if the unsafe condition has not

been eliminated, the request should include

specific proposed actions to address it.

Compliance: Required as indicated, unless

accomplished previously.

To prevent structural damage to the tail

section when it strikes the runway, which

could result in depressurization of the

fuselage during flight, accomplish the

following:

Restatement of Requirement of AD 97–08–04

(a) For airplanes listed in Airbus Service

Bulletin A320–53–1110, dated August 28,

1995: Within 6 years after May 15, 1997 (the

effective date of AD 97–08–04, amendment

39–9992), modify the fuselage by reinforcing

frames 68 and 69 in accordance with Airbus

Service Bulletin A320–53–1110, dated

August 28, 1995; or Revision 1, dated

November 27, 1995.

New Requirements of this AD

(b) For airplanes other than those

identified in paragraph (a) of this AD: Within

5 years after the effective date of this AD,

modify the fuselage by reinforcing frames 68

and 69 in accordance with Airbus Service

Bulletin A320–53–1110, dated August 28,

1995, or Revision 1, dated November 27,

1995.

(c) For all airplanes: Within 5 years after

the effective date of this AD, modify the

fuselage by reinforcing frames 65 to 67 in

accordance with Airbus Service Bulletin

A320–53–1131, dated July 24, 1997.

(d) An alternative method of compliance or

adjustment of the compliance time that

provides an acceptable level of safety may be

used if approved by the Manager,

International Branch, ANM–116, FAA,

Transport Airplane Directorate. Operators

shall submit their requests through an

appropriate FAA Principal Maintenance

Inspector, who may add comments and then

send it to the Manager, International Branch,

ANM–116.

Note 2: Information concerning the

existence of approved alternative methods of

compliance with this AD, if any, may be

obtained from the International Branch,

ANM–116.

(e) Special flight permits may be issued in

accordance with sections 21.197 and 21.199

of the Federal Aviation Regulations (14 CFR

21.197 and 21.199) to operate the airplane to

a location where the requirements of this AD

can be accomplished.

Note 3: The subject of this AD is addressed

in French airworthiness directive 97–315–

109(B), dated October 22, 1997.

Issued in Renton, Washington, on July 1,

1998.

Stewart R. Miller,

Acting Manager, Transport Airplane

Directorate, Aircraft Certification Service.

[FR Doc. 98–18157 Filed 7–8–98; 8:45 am]

BILLING CODE 4910–13–U

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 97–NM–92–AD]

RIN 2120–AA64

Airworthiness Directives; Mitsubishi

Model YS–11 Series Airplanes

AGENCY: Federal Aviation

Administration, DOT.

ACTION: Notice of proposed rulemaking

(NPRM).

SUMMARY: This document proposes the

adoption of a new airworthiness

directive (AD) that is applicable to all

Mitsubishi Model YS–11 series

airplanes. This proposal would require

repetitive inspections to detect fatigue

cracking in the manhole doublers of the

lower wing panels; and repair, if

necessary. This proposal also would

require eventual modification of screw

holes in the manhole doublers of the

lower wing panels. This proposal is

prompted by issuance of mandatory

continuing airworthiness information by

a foreign civil airworthiness authority.

The actions specified by the proposed

AD are intended to detect and correct

fatigue cracking in the manhole

doublers of the lower wing panels,

which could result in failure of the wing

structure.

DATES: Comments must be received by

August 10, 1998.

ADDRESSES: Submit comments in

triplicate to the Federal Aviation

Administration (FAA), Transport

Airplane Directorate, ANM–114,

Attention: Rules Docket No. 97–NM–

92–AD, 1601 Lind Avenue, SW.,

Renton, Washington 98055–4056.

Comments may be inspected at this

location between 9:00 a.m. and 3:00

p.m., Monday through Friday, except

Federal holidays.

The service information referenced in

the proposed rule may be obtained from

Nihon Aeroplane Manufacturing,

Toranomon Daiichi, Kotohire-Cho,

Shiba, Minato-Ku, Tokyo, Japan. This

information may be examined at the

FAA, Transport Airplane Directorate,

1601 Lind Avenue, SW., Renton,

Washington; or at the FAA, Transport

Airplane Directorate, Los Angeles

Aircraft Certification Office, 3960

Paramount Boulevard, Lakewood,

California.

FOR FURTHER INFORMATION CONTACT:

William Roberts, Aerospace Engineer,

Airframe Branch, ANM–120L, FAA,

Transport Airplane Directorate, Los

Angeles Aircraft Certification Office,

3960 Paramount Boulevard, Lakewood,

California 90712–4137; telephone (562)

627–5228; fax (562) 627–5210.

SUPPLEMENTARY INFORMATION:

Comments Invited

Interested persons are invited to

participate in the making of the

proposed rule by submitting such

written data, views, or arguments as

they may desire. Communications shall

identify the Rules Docket number and

be submitted in triplicate to the address

specified above. All communications

received on or before the closing date

for comments, specified above, will be

considered before taking action on the

proposed rule. The proposals contained
Federal Register / Vol. 63, No. 131 /Thursday, July 9, 1998 / Proposed Rules 37081

in this notice may be changed in light

of the comments received.

Comments are specifically invited on

the overall regulatory, economic,

environmental, and energy aspects of

the proposed rule. All comments

submitted will be available, both before

and after the closing date for comments,

in the Rules Docket for examination by

interested persons. A report

summarizing each FAA-public contact

concerned with the substance of this

proposal will be filed in the Rules

Docket.

Commenters wishing the FAA to

acknowledge receipt of their comments

submitted in response to this notice

must submit a self-addressed, stamped

postcard on which the following

statement is made: ‘‘Comments to

Docket Number 97–NM–92–AD.’’ The

postcard will be date stamped and

returned to the commenter.

Availability of NPRMs

Any person may obtain a copy of this

NPRM by submitting a request to the

FAA, Transport Airplane Directorate,

ANM–114, Attention: Rules Docket No.

97–NM–92–AD, 1601 Lind Avenue,

SW., Renton, Washington 98055–4056.

Discussion

The Japan Civil Aviation Bureau

(JCAB), which is the airworthiness

authority for Japan, notified the FAA

that an unsafe condition may exist on

all Mitsubishi Model YS–11 series

airplanes. The JCAB advises that, during

fatigue testing performed by the

manufacturer, fatigue cracking was

detected in the manhole doublers of a

lower wing panel after 52,600 total

flight cycles. The cracking has been

attributed to stress concentrations

caused by the manhole cutout and the

screw holes. Cracks propagated quickly

and also developed in the outer panel

and stringer. Such fatigue cracking, if

not detected and corrected, could

progress to the wing skins and result in

failure of the wing structure.

Explanation of Relevant Service

Information

Mitsubishi has issued Nihon

Aeroplane Manufacturing Company

(NAMC) YS–11 Service Bulletin 57–77,

Revision 2, dated September 14, 1994,

which describes procedures for

repetitive visual inspections to detect

fatigue cracking in the manhole

doublers of the lower wing panels;

repair, if necessary; and modification of

screw holes in the manhole doublers of

the lower wing panels. The modification

involves a fluorescent penetrant or highfrequency eddy current inspection to

detect cracking in the manhole doublers

and screw holes, cold working (cold

expansion) of the screw holes, and

follow-on actions to prevent corrosion.

(These follow-on actions include

applying primer, anticorrosive, and

sealant.) Accomplishment of the actions

specified in the service bulletin is

intended to adequately address the

identified unsafe condition.

The JCAB classified this service

bulletin as recommended and issued

Japanese airworthiness directive TCD–

3795–2–96, dated December 13, 1996, in

order to assure the continued

airworthiness of these airplanes in

Japan.

Mitsubishi also has issued NAMC

YS–11 Supplemental Inspection

Document (SID) Publication Number

YS-MR–201, dated November 11, 1994.

Inspection Item 57–00–03 of the SID

(hereinafter referred to as ‘‘the SID

item’’) describes procedures for

repetitive visual inspections to detect

fatigue cracking in the manhole

doublers of the lower wing panels.

These inspections essentially are

equivalent to the repetitive visual

inspections that would be required by

this proposed AD. The JCAB approved

the SID; however, the FAA has not been

informed of the issuance of a Japanese

airworthiness directive that would

require accomplishment of the SID

program for these airplanes in Japan.

FAA’s Conclusions

This airplane model is manufactured

in Japan and is type certificated for

operation in the United States under the

provisions of section 21.29 of the

Federal Aviation Regulations (14 CFR

21.29) and the applicable bilateral

airworthiness agreement. Pursuant to

this bilateral airworthiness agreement,

the JCAB has kept the FAA informed of

the situation described above. The FAA

has examined the findings of the JCAB,

reviewed all available information, and

determined that AD action is necessary

for products of this type design that are

certificated for operation in the United

States.

Explanation of Requirements of

Proposed Rule

Since an unsafe condition has been

identified that is likely to exist or

develop on other airplanes of the same

type design registered in the United

States, the proposed AD would require

accomplishment of the actions specified

in the service bulletin described

previously, except as discussed below.

Differences Between Proposed Rule,

Service Information, and Japanese

Airworthiness Directive

Operators should note that the SID

item, described previously, specifies

accomplishment of certain inspections

that are equivalent to those that would

be required by this proposed AD.

However, because the inspections

described in the SID have not been

mandated previously by the FAA, and

because failure to detect fatigue cracking

in this area could result in the unsafe

condition described previously, the

FAA has determined that it is necessary

to require accomplishment of these

inspections, as well as modification of

the affected area, via this proposed AD,

in order to ensure the continued

operational safety of these airplanes.

Operators also should note that the

service bulletin and the Japanese

airworthiness directive, described

previously, specify that accomplishment

of the modification eliminates the need

for the repetitive inspections described

in the service bulletin. However, the SID

item provides for continued inspections

following accomplishment of the

modification. Therefore, this proposed

AD requires repetitive inspections after

accomplishment of the modification

proposed by this AD.

Operators also should note that,

although the service bulletin and the

Japanese airworthiness directive specify

accomplishment of the initial inspection

prior to the accumulation of 60,000 total

flight cycles, with a repetitive interval of

2,000 flight cycles, the SID item

provides for an initial inspection prior

to the accumulation of 45,000 total

flight cycles and a repetitive inspection

interval of 8,000 flight cycles. Following

accomplishment of the modification

described in the service bulletin, the

SID item specifies that the repetitive

interval is reduced to 6,000 flight cycles.

In light of the compliance times

recommended in the SID item, the FAA

finds that the initial inspection must be

accomplished prior to the accumulation

of 45,000 total flight cycles. However,

the FAA has determined that an

inspection interval of 6,000 flight cycles

is appropriate, both before and after

accomplishment of the modification

specified in the service bulletin.

Additionally, operators should note

that the Japanese airworthiness directive

specifies that modification of the screw

holes in the manhole doublers of the

lower wing panels be accomplished

prior to the accumulation of 60,000 total

flight cycles, or before December 13,

2000 (four years after the effective date

of the Japanese airworthiness directive),

whichever occurs later. In developing
37082 Federal Register / Vol. 63, No. 131 /Thursday, July 9, 1998 / Proposed Rules

an appropriate compliance time for this

proposed AD, the FAA considered not

only the safety implications and the

JCAB’s recommendations, but also the

manufacturer’s recommendations. The

manufacturer recommended

accomplishment of the modification

prior to the accumulation of 60,000 total

flight cycles, or January 8, 1997 (four

years after the issuance of the original

service bulletin). The FAA also

considered the fact that the referenced

version of the service bulletin (which

contains the procedures for

accomplishing the required

modification) has been available to all

operators of Mitsubishi YS–11 series

airplanes since September 1994. In light

of all of these factors, the FAA finds that

the modification must be accomplished

prior to the accumulation of 60,000 total

flight cycles, which represents an

appropriate interval of time allowable

for affected airplanes to continue to

operate without compromising safety.

Cost Impact

The FAA estimates that 25 airplanes

of U.S. registry would be affected by this

proposed AD.

It would take approximately 30 work

hours per airplane to accomplish the

proposed inspection, at an average labor

rate of $60 per work hour. Based on

these figures, the cost impact of the

inspection proposed by this AD on U.S.

operators is estimated to be $45,000, or

$1,800 per airplane, per inspection

cycle.

It would take approximately 40 work

hours per airplane to accomplish the

proposed modification, at an average

labor rate of $60 per work hour. Based

on these figures, the cost impact of the

modification proposed by this AD on

U.S. operators is estimated to be

$60,000, or $2,400 per airplane.

The cost impact figures discussed

above are based on assumptions that no

operator has yet accomplished any of

the proposed requirements of this AD

action, and that no operator would

accomplish those actions in the future if

this AD were not adopted.

Regulatory Impact

The regulations proposed herein

would not have substantial direct effects

on the States, on the relationship

between the national government and

the States, or on the distribution of

power and responsibilities among the

various levels of government. Therefore,

in accordance with Executive Order

12612, it is determined that this

proposal would not have sufficient

federalism implications to warrant the

preparation of a Federalism Assessment.

For the reasons discussed above, I

certify that this proposed regulation (1)

is not a ‘‘significant regulatory action’’

under Executive Order 12866; (2) is not

a ‘‘significant rule’’ under the DOT

Regulatory Policies and Procedures (44

FR 11034, February 26, 1979); and (3) if

promulgated, will not have a significant

economic impact, positive or negative,

on a substantial number of small entities

under the criteria of the Regulatory

Flexibility Act. A copy of the draft

regulatory evaluation prepared for this

action is contained in the Rules Docket.

A copy of it may be obtained by

contacting the Rules Docket at the

location provided under the caption

ADDRESSES.

List of Subjects in 14 CFR Part 39

Air transportation, Aircraft, Aviation

safety, Safety.

The Proposed Amendment

Accordingly, pursuant to the

authority delegated to me by the

Administrator, the Federal Aviation

Administration proposes to amend part

39 of the Federal Aviation Regulations

(14 CFR part 39) as follows:

PART 39—AIRWORTHINESS

DIRECTIVES

1. The authority citation for part 39

continues to read as follows:

Authority: 49 U.S.C. 106(g), 40113, 44701.

§ 39.13 [Amended]

2. Section 39.13 is amended by

adding the following new airworthiness

directive:

Mitsubishi Heavy Industries, Ltd.: Docket

97–NM–92–AD.

Applicability: All Model YS–11 series

airplanes, certificated in any category.

Note 1: This AD applies to each airplane

identified in the preceding applicability

provision, regardless of whether it has been

modified, altered, or repaired in the area

subject to the requirements of this AD. For

airplanes that have been modified, altered, or

repaired so that the performance of the

requirements of this AD is affected, the

owner/operator must request approval for an

alternative method of compliance in

accordance with paragraph (c) of this AD.

The request should include an assessment of

the effect of the modification, alteration, or

repair on the unsafe condition addressed by

this AD; and, if the unsafe condition has not

been eliminated, the request should include

specific proposed actions to address it.

Compliance: Required as indicated, unless

accomplished previously.

To detect and correct fatigue cracking in

the manhole doublers of the lower wing

panels, which could result in failure of the

wing structure, accomplish the following:

(a) Perform a visual inspection to detect

cracking in the manhole doublers and around

the screw holes of the lower wing panels, in

accordance with Mitsubishi Nihon Aeroplane

Manufacturing Company (NAMC) Service

Bulletin 57–77, Revision 2, dated September

14, 1994, at the time specified in either

paragraph (a)(1) or (a)(2) of this AD, as

applicable. Repeat the inspection thereafter

at intervals not to exceed 6,000 flight cycles.

(1) For airplanes that have accumulated

fewer than 45,000 total flight cycles as of the

effective date of this AD: Prior to the

accumulation of 45,000 total flight cycles, or

within 1 year after the effective date of this

AD, whichever occurs later, perform the

initial inspection.

(2) For airplanes that have accumulated

45,000 or more total flight cycles as of the

effective date of this AD: Within 2,000 flight

cycles or 1 year after the effective date of this

AD, whichever occurs first, perform the

initial inspection.

(b) Modify the screw holes in the manhole

doublers of the lower wing panels, in

accordance with Mitsubishi NAMC Service

Bulletin 57–77, Revision 2, dated September

14, 1994, at the applicable time specified in

either paragraph (b)(1) or (b)(2) of this AD.

Thereafter, if any cracking is found, prior to

further flight, repair the cracking in

accordance with the service bulletin.

Note 2: Accomplishment of the

modification specified in paragraph (b) does

not constitute terminating action for the

repetitive inspections of paragraph (a).

(1) If no cracking is found, prior to the

accumulation of 60,000 total flight cycles, or

within 1 year after the effective date of this

AD, whichever occurs later, accomplish the

modification in accordance with the service

bulletin.

(2) If any cracking is found, prior to further

flight, repair the cracking and accomplish the

modification, in accordance with the service

bulletin.

(c) An alternative method of compliance or

adjustment of the compliance time that

provides an acceptable level of safety may be

used if approved by the Manager, Los

Angeles Aircraft Certification Office (ACO),

FAA, Transport Airplane Directorate.

Operators shall submit their requests through

an appropriate FAA Principal Maintenance

Inspector, who may add comments and then

send it to the Manager, Los Angeles ACO.

Note 3: Information concerning the

existence of approved alternative methods of

compliance with this AD, if any, may be

obtained from the Los Angeles ACO.

(d) Special flight permits may be issued in

accordance with sections 21.197 and 21.199

of the Federal Aviation Regulations (14 CFR

21.197 and 21.199) to operate the airplane to

a location where the requirements of this AD

can be accomplished.

Note 4: The subject of this AD is addressed

in Japanese airworthiness directive TCD–

3795–2–96, dated December 13, 1996.

Issued in Renton, Washington, on July 1,

1998.

Stewart R. Miller,

Acting Manager, Transport Airplane

Directorate, Aircraft Certification Service.

[FR Doc. 98–18156 Filed 7–8–98; 8:45 am]

BILLING CODE 4910–13–U